
#include <sys/param.h>
#include <sys/sched.h>
#ifdef _KERNEL
#include <sys/kmem.h>
#include <lib/libkern/libkern.h>
#include <sys/atomic.h>
#else
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <sys/sysctl.h>
#endif

#define	CPUSET_SHIFT	5
#define	CPUSET_MASK	31
#define CPUSET_NENTRIES(nc)	((nc) > 32 ? ((nc) >> CPUSET_SHIFT) : 1)
#ifndef __lint__
#define CPUSET_SIZE(n)	(sizeof( \
	struct {  \
		uint32_t bits[0]; \
	}) + sizeof(uint32_t) * (n))
#else
#define CPUSET_SIZE(n)	0
#endif

struct _cpuset {
	uint32_t	bits[0];
};

#ifndef _KERNEL

static size_t cpuset_size = 0;
static size_t cpuset_nentries = 0;

size_t
/*ARGSUSED*/
_cpuset_size(const cpuset_t *c)
{

	return cpuset_size;
}

void
_cpuset_zero(cpuset_t *c)
{

	memset(c->bits, 0, cpuset_nentries * sizeof(c->bits[0]));
}

int
_cpuset_isset(cpuid_t i, const cpuset_t *c)
{
	const unsigned long j = i >> CPUSET_SHIFT;

	if (j >= cpuset_nentries) {
		errno = EINVAL;
		return -1;
	}
	return ((1 << (unsigned int)(i & CPUSET_MASK)) & c->bits[j]) != 0;
}

int
_cpuset_set(cpuid_t i, cpuset_t *c)
{
	const unsigned long j = i >> CPUSET_SHIFT;

	if (j >= cpuset_nentries) {
		errno = EINVAL;
		return -1;
	}
	c->bits[j] |= 1 << (unsigned int)(i & CPUSET_MASK);
	return 0;
}

int
_cpuset_clr(cpuid_t i, cpuset_t *c)
{
	const unsigned long j = i >> CPUSET_SHIFT;

	if (j >= cpuset_nentries) {
		errno = EINVAL;
		return -1;
	}
	c->bits[j] &= ~(1 << (unsigned int)(i & CPUSET_MASK));
	return 0;
}

cpuset_t *
_cpuset_create(void)
{

	if (cpuset_size == 0) {
		static int mib[2] = { CTL_HW, HW_NCPU };
		size_t len;
		u_int nc;

		len = sizeof(nc);
		if (sysctl(mib, (unsigned int)__arraycount(mib), &nc, &len,
		    NULL, 0) == -1)
			return NULL;

		cpuset_nentries = CPUSET_NENTRIES(nc);
		cpuset_size = CPUSET_SIZE(cpuset_nentries);
	}
	return calloc(1, cpuset_size);
}

void
_cpuset_destroy(cpuset_t *c)
{

	free(c);
}

#endif
#endif
